Re: [PATCH 22/40] mips,kgdb: kdb low level trap catch and stack trace

[David Daney <ddaney@caviumnetworks.com>]

Jason Wessel wrote:
> The only way the debugger can handle a trap in inside rcu_lock,
> notify_die, or atomic_notifier_call_chain without a recursive fault is
> to have a low level "first opportunity handler" do_trap_or_bp() handler.
> 
> Generally this will be something the vast majority of folks will not
> need, but for those who need it, it is added as a kernel .config
> option called KGDB_LOW_LEVEL_TRAP.
> 
> Also added was a die notification for oops such that kdb can catch an
> oops for analysis.
> 
> There appeared to be no obvious way to pass the struct pt_regs from
> the original exception back to the stack back tracer, so a special
> case was added to show_stack() for when kdb is active because you
> generally desire to generally look at the back trace of the original
> exception.
> 
> CC: Ralf Baechle <ralf@linux-mips.org>
> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
> ---
>  arch/mips/include/asm/kgdb.h |    2 ++
>  arch/mips/kernel/kgdb.c      |   22 +++++++++++++++++++++-
>  arch/mips/kernel/traps.c     |   14 ++++++++++++++
>  lib/Kconfig.kgdb             |    2 +-
[...]
> +#include "../../../kernel/debug/kdb/kdb_private.h"
>  

There must be a better way of referring to this include file.  Perhaps 
it should be moved to a more central place that is already in the 
include path so we can refer to it with #include <.../file.h>

David Daney